Supernanny faces a tough assignment when she agrees to move into the home of single mum Kelly Steer. Kelly's two young children have pretty much destroyed the family home. Out of control four year old Callum and five year old Sophia dominate the house. They fight with each other, won't eat properly, destroy their bedrooms, refuse to sleep at bedtime, and worst of all, they have been known to physically attack their mum. Supernanny wastes no time enforcing a massive family rethink, beginning with a major tidy-up. Tears and tantrums are in full force as a new and strict routine is introduced. Even mum Kelly finds it hard. Will it all prove too much for the Steers?